fix(acp): restore output_rx on every do_prompt exit path - #6665
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do_prompt only restored entry.output_rx on the success path after drain_agent_events completed. An input_tx.send failure, or the turn's task being aborted while suspended inside drain_agent_events, left the receiver permanently unrestored, wedging the session with "prompt already in progress" on every subsequent request. A PromptChannelGuard now owns the receiver for the whole do_prompt call and restores it on Drop, covering every exit path; drain_agent_events borrows the receiver instead of consuming it so the guard never loses ownership across the drain loop's await points.
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* docs(readme): sync crate READMEs with commits since v0.22.3 Reconciles all 24 changed crate READMEs against the actual shipped implementation for the v0.22.3..HEAD range: new subsystems (risk-chain detection, capability scoping, plugin dependency graph, session spawn cap), several pre-existing factual errors unrelated to this release (inverted file-sandbox precedence, fabricated MCP config keys, wrong anomaly-detector defaults, stale trust-level names), and terminology/ API renames that had drifted out of sync with the code. * docs(specs): reconcile spec drift for commits since v0.22.3 Closes drift left after the skill-quarantine trust fixes (#6701, #6702, #6706, #6707, #6713), the subagent session-wide spawn cap (#6545), four post-ACP-2.0.0-migration bugfixes (#6660, #6665, #6672, #6684), the mention-picker and TUI interrupt-hint updates, the MAX_RETRY_SECS compile-time bound, the sanitizer secret-shape masking extension, the tracing-guard-flush invariants, and the VigilGate per-process pattern-compile fix. Updates specs/README.md's index to match. * docs(book): sync user docs with commits since v0.22.3 Updates the TUI keybindings and mention-picker pages for the new Ctrl+C semantics, the inline @ mention picker, and the input separator's busy indicator; documents the new [tools.shell] risk_chain_window_turns config key; corrects the ACP protocol version reference (was stale at 0.11.1); bumps the sub-agent frontmatter breaking-change note to v0.22.4. * fix(serve): give build_combined_deps_wires_policy_gate test a dedicated stack cargo nextest run --features full could crash with a stack overflow (SIGABRT) on serve::agent_factory::tests::build_combined_deps_wires_policy_gate_through_to_session_agent. Same defect class already fixed once in this file for issue #6699: building a full Agent under --features full's unboxed AnyProvider variants (Candle/Gonka/Cocoon) reaches the same VigilGate::try_new stack depth that overflows the default 2 MiB test-thread stack in an unoptimized build. The #6699 fix only wrapped the one test it was filed against, leaving this one - added in PR #6007, unrelated to any change in this release - unprotected. CI's test job never caught it because it runs the curated feature set, not full, so the deeper AnyProvider frames never materialize there. Runs the test body on a dedicated 32 MiB-stack thread instead of directly under #[tokio::test], reusing the existing TEST_THREAD_STACK_SIZE constant. * release: prepare v0.22.4 Bump version across the workspace, finalize the CHANGELOG.md [0.22.4] section, refresh the README tests badge, and re-accept the splash-screen snapshots (embed the version string).
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Summary
do_prompt(crates/zeph-acp/src/agent/turn.rs) only restoredentry.output_rxon the success path afterdrain_agent_eventscompleted. Aninput_tx.sendfailure returned early without restoring it, and the enclosing task being aborted while suspended insidedrain_agent_events(reachable since ACP permission gate deadlocks on every permission-gated tool call #6656 spawns the turn instead of awaiting it inline) dropped the receiver entirely — both permanently wedged the session with "prompt already in progress" on every subsequentsession/promptcall.PromptChannelGuard, an RAII guard that owns the session'soutput_rxreceiver for the entiredo_promptcall and restores it into the session onDrop, covering every exit path (normal return, early return, task abort/drop).drain_agent_eventsto borrow&mut mpsc::Receiver<LoopbackEvent>instead of consuming it by value, so the guard never loses ownership across the drain loop's await points.Closes #6661
Test plan
input_tx_send_failure_does_not_wedge_session— reproduces the issue's literal repro (dropped agent-loop channel causesinput_tx.sendfailure), asserts the specific"agent channel closed"error, and confirms the session recovers (acquire_prompt_channelssucceeds afterward).abort_mid_drain_does_not_wedge_session— spawnsdo_prompt, deterministically parks it insidedrain_agent_events'srx.recv(), aborts the task, and confirms the session recovers.two_consecutive_prompts_succeed_without_wedging_session— happy-path non-regression check.cargo +nightly fmt --checkcleancargo clippy --profile ci --workspace --all-targets --features "desktop,ide,server,chat,pdf,scheduler,testing" -- -D warningscleancargo nextest run --config-file .github/nextest.toml --workspace --features "desktop,ide,server,chat,pdf,scheduler" --lib --bins— full suite greenRUSTFLAGS="-D warnings" RUSTDOCFLAGS="--deny rustdoc::broken_intra_doc_links" cargo doc --no-deps --workspace --features "desktop,ide,server,chat,pdf,scheduler") cleansignificantinitially (2 test gaps), both resolved and re-verifiedapproved, full CI-matching suite independently re-run